[CPMD-list] (no subject)

[davidofkozlowski]

Dear all,

We would like to calculate the BDE of phenol in water. To perform  
such calculation with a large numbers of water molecules, we believe  
that CPMD offers the best possibility.
However this is a new technique for us, so we would appreciate some  
help with the following questions.

1st question : Which are the best functionals and pseudopotentials  
for radicals? In standard DFT calculations hybrid B3LYP is known to  
underestimate the BDE.

2nd question : When using MT pseudopotential a large cutoff (70 ry)  
is required. If we run calculations (PBC) of phenol with only the  
first solvation shell (12x12x10) is it possible that the solute  
interacts with its image?

3rd question : We know that CPMD calculations can yield the Helmholtz  
Free Energy (DeltaA or DeltaF) ) but we require the enthalpy (DeltaH)  
to calculate the BDE. Is there an easy way to convert one to the  
other or to obtain DeltaH directly ?

Thank you for any suggestions.